The amount of energy released for the process $X_{(g)} + e^- \to X^-_{(g)}$ is minimum and maximum respectively for :-
$(a) \ F$
$(b) \ Cl$
$(c) \ N$
$(d) \ B$
Correct answer is :-

Electron affinity is the lowest for

Which one of the following statements is incorrect?

Assertion $(A)$: Fluorine has a smaller negative electron gain enthalpy than chlorine.
Reason $(R)$: The electron-electron repulsion is higher in chlorine than in fluorine.

The formation of oxide ion $O^{2-}$ from oxygen atom requires an exothermic reaction,followed by an endothermic step as shown below. The process of formation of $O^{2-}$ in gas phase is unfavorable $(\Delta H^{\ominus} = +ve)$,even though it has the stable configuration of the nearest noble gas neon. This is because:
$O_{(g)} + e^{-} \longrightarrow O^{-}_{(g)} ; \Delta H^{\ominus} = -141 \ kJ \ mol^{-1}$
$O^{-}_{(g)} + e^{-} \longrightarrow O^{2-}_{(g)} ; \Delta H^{\ominus} = +760 \ kJ \ mol^{-1}$

The process requiring absorption of energy is